netdev - Re: SO_REUSEPORT - can it be done in kernel?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20110228042620.GA16224@gondor.apana.org.au>
Date:	Mon, 28 Feb 2011 12:26:20 +0800
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Tom Herbert <therbert@...gle.com>
Cc:	David Miller <davem@...emloft.net>, rick.jones2@...com,
	wsommerfeld@...gle.com, daniel.baluta@...il.com,
	netdev@...r.kernel.org
Subject: Re: SO_REUSEPORT - can it be done in kernel?

On Sun, Feb 27, 2011 at 07:45:55PM -0800, Tom Herbert wrote:
> That sounds promising, but receive side will still have problems.
> There is lock contention on the queue as well as cache line bouncing
> on the sock structures.  Also multiple threads sleeping on same socket
> typically leads to asymmetric load across the threads (and
> degenerative cases where receiving thread is woken up and other
> threads have already processed all the packets).  TCP listener threads
> suffer from these same problems.

IOW this is something that we have to solve anyway.  I'm just
being overly cautious here because user-space API changes are
something that we should not enter into lightly.

If this patch was completely internal to the kernel, then I would
have much less of an objection as we can always revert/change it
later on.  With a user-space API we don't have that flexibility.

Thanks,
-- 
Email: Herbert Xu <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html